talilc. The figure in tbc second column represents the maximum dimension — as a rule the 

 height, but e. g. in specimen 1847 tfig. 8j the distance between the two extremities. In the 

 lust column are the running numbers of the specimens : 163 a to 1857 for P. earina/a, 660 a 

 to 1853 for P. melobesioides. 



Colour. In the fourth column of the above table we have noted the colour of 

 Placospoiigia melobesioides and carinata, judged from the material preserved in alcohol. But 

 Professor Weber informs us that the specimens had about the same colour when alive. 

 It seems that all the known species of Placospongia appear in two colours, viz. purplish red 

 and pale buff. The two specimens from which Gray originally made his description were 

 "chalky white" and "pale purplish red." The purplish red we observe in various shades, lighter 

 or darker, more bluish or brownish red, etc, etc. A very remarkable fact it is, observed already 

 by Thiele (1899 P- 9)ï tnat re d specimens, when quite dry, have a pale buff or dirty white 

 colour, which again turns red after moistening. We shall see presently that the red colour resides 

 in the sterrospirae. A few specimens (e. g. 311 e) show white (i. e. pale) portions amidst the 

 general red colour. The above mentioned grooves are of a yellowish colour. 



1) * Entire, uninjured specimens. 



